Decimal Oscilloclock harks back to 1927 movie

Metropolis is a classic, silent film produced in 1927 and was one of the very first full length feature films of the science fiction genre, and very influential. (C-3PO was inspired by Maria, the “Machine human” in Metropolis.) Within the first couple of minutes in the film, we get to see two clocks — one with a 24-hour dial and another larger one with a 10-hour dial. The human overlords of Metropolis lived a utopian 24 hour day, while the worker scum who were forced to live and work underground, were subjected to work in two ten-hour shifts during the same period.

[Aaron]’s client was setting up a Metropolis themed man-cave and commissioned him to build a Metropolis Oscilloclock which would not only show the 24 hour and 10 hour clocks from the film, but also accurately reproduce the clock movements and its fonts. [Aaron]’s Oscilloclock is his latest project in the series of bespoke CRT clocks which he has been building since he was a teen.

The clock is built around a Toshiba ST-1248D vintage oscilloscope that has been beautifully restored. There are some modern additions – such as LED glow indicators for the various valves and an external X-Y input to allow rendering Lissajous figures on the CRT. He’s also added some animations derived from the original poster of the film. Doing a project of this magnitude is not trivial and its taken him almost eight months to bring it from concept to reality. We recommend looking through some of his other blog posts too, where he describes how oscilloclocks work, how he builds the HV power supplies needed to drive the CRT’s, and how he ensures vibration and noise damping for the cooling fans used for the HV power supplies. It’s this attention to detail which results in such well-built clocks. Check out some of [Aaron]’s other awesome Oscilloclock builds that we have featured over the years.

The film itself has undergone several restoration attempts, with most of it being recovered from prints which were discovered in old archives. If you wish to go down that rabbit hole, check out Wikipedia for more details and then head over to YouTube where several versions appear to be hosted.

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Fail of the week : Watt a loss

This one is a bit dated, but the lessons are still relevant. [Zach Hoeken] posted about the challenges he faced building a CNC stepper driver. He was experimenting with Toshiba motor drivers back in 2012.

The modular motor driver boards he built were based on the THB6064AH – capable of 1/64th step, and 4.5 Amps at up to 50V. [Zach] built a test jig to run the boards through their paces. A couple of messed tracks was the least of his problems – easily fixed by cutting traces and using jumper wires to correct the errors. But the header footprints for the motor drive boards got reversed. The only way out was to solder the headers on the back side.

LESSON : Always check footprint orientation and pin numbering before sending boards to fab.

The surprising part was when someone as experienced as [Zach] messed up on Ohms Law. Based on the current he wanted the motors to run at, his sense resistors needed to be 3.2W, but he’d used SMD footprints (0805 likely) instead. Those tiny resistors couldn’t be used at all, and the 5W resistors plonked on looked like an ugly hack.

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Fixing that broken laptop power jack

It seems that there’s a whole range of Toshiba Satellite laptop computers that suffer from a power jack design that is prone to breaking. We see some good and some bad in this. The jack is not mounted to the circuit board, so if it gets jammed into the body like the one above it doesn’t hose the electronics. But what has happened here is the plastic brackets inside the case responsible for keeping the jack in place have failed. You won’t be able to plug in the power adapter unless you figure out a way to fix it.

We’d wager the hardest part of this repair is getting the case open. Once inside, just cut away all of the mangled support tabs to make room for the replacement jack. The one used here has a threaded cuff that makes it a snap to mount the new part to the case. Clip off the old jack and solder the wires (mind the polarity!) and you’re in business.

Anyone know why we don’t see more of the magnetic connectors (MagSafe) that the Apple laptops have? Is it a patent issue?

[Thanks Dan]

Commercial webcam multi-touch coming soon

It looks like Toshiba has a webcam-based multi-touch display on the way. The video shows an iPod-esque photos album interface where the user stands in front of the display and manipulates it with both hands. The difference between this and some of the other multi-touch displays we’ve seen is that there is no touching necessary (goodbye fingerprints!). The user’s image is superimposed on the screen in a way that reminds us of the original Playstation Eye. Obviously this is much more refined, making us wonder if it’s the better camera, better processing, or both.

[Thanks Risingsun]